OTHER PROJECT INFORMATION ? PROJECT SUMMARY/ABSTRACT This proposal is a renewal for the tremendously successful two-day symposium ?Chemistry and Pharmacology of Drugs of Abuse? (CPDA) symposium that first took place in 2016 under the auspices of the Center for Drug Discovery (CDD), Northeastern University, Boston, Massachusetts. The primary aim of the symposium is to serve as an interdisciplinary exposition of the most recent, important, research-related advances in (pre)clinical research related to Substance Use Disorder (SUD). Substance Use Disorders (SUDs) and addiction are pervasive threats to global public health and the nature of the threat is ever evolving and changing. Our goal is to address gaps in current knowledge concerning SUD disease mechanisms and treatments that are at the root of our limitations in solving these medical challenges. A major theme is the integration of medicinal chemistry, structural biology, pharmacology, behavioral pharmacology and clinical practice to inform the design, synthesis, optimization, and (pre)clinical profiling of new agents for their therapeutic potential. SUD biology and etiology are complex. Behavioral, environmental, and (epi)genetic factors conspire to modulate neuronal circuits to affect vulnerability, cognition, social behavior, and emotional state in ways that help establish a SUD phenotype. The details of these neurobiological processes are not well understood. In addition, better standardized animal paradigms of drug-seeking and -taking are required that better model clinical SUD pathology and can be used to accurately assess the potential of novel SUD drugs. Despite significant advances, there is a frustratingly limited number of safe and affective pharmacotherapies available to attain durable abstinence. Our continuing aim is to focus the meeting entirely on Substance Use Disorder and bring together leading practitioners from each of these fields. Moreover, there are emergent threats to at-risk SUD populations such as ?designer drugs? that lack affective pharmacotherapy and require ongoing vigilance and effort to combat. We aim to include topics that address emergent issues in each year?s program as identified by NIDA community leaders and leading research. Such a gathering offers a rich opportunity to expose young scientists to the field. We aim to inspire and encourage the next generation of researchers to devote themselves to this endeavor. We have made considerable efforts to welcome scientists from underserved and underrepresented populations and we aim to expand these efforts. A focused meeting on SUD responsive to emergent threats is of high value and has garnered much support by the SUD research community and diverse constituencies, from basic researchers to healthcare providers and public-health officials. This included scientists from biotechnology (e.g. Astraea Therapeutics), leading biomedical research centers (e.g. Scripps Research Institute), research-intensive clinical centers (e.g., McLean Hospital/Harvard Medical School, Icahn School of Medicine at Mount Sinai) and representatives from the City of Boston Mayor?s office. Our goal is to further raise the public profile of our symposium.